Dr. Steven Bratman — once an alternative medicine practitioner, now an urgent care doctor — coined the term "orthorexia" in response to patients who were avoiding more and more foods. When we spoke on the phone, he said, "the typical refrain, week after week, was: I'm not feeling well in such-and-such a way, what else should I cut out of my diet?" But when he told one patient she had an eating disorder because she had restricted herself to 15 foods, "she thought that was a joke, because how could eating healthy be an eating disorder?" Bratman decided to give orthorexia a clinical-sounding name in order to combat the fact that "people saw it as a virtue."

Now that his term has taken on a life of its own, he's a bit skeptical. He says that while many people are probably "overly-obsessed with diet" and "should lighten up a little," those who truly endanger their health in a quest for dietary purity are probably rare. He speculates that orthorexia could be a variant of obsessive-compulsive disorder rather than anorexia, and adds that the disorder has "a religious quality to it." He points to extreme raw-foodism, some of whose adherents teach "that the great enemy of man is the cooking stove," as an example of such religiosity. Given that food has become so deeply moralized in our culture, it's no surprise that some might approach eating almost religiously — or that a few of those who do might take the practice to dangerous extremes.

The most interesting part of our conversation, though, was Bratman's assertion that "I'm not actually sure there is such a things as unhealthy food." He clarified that it "is probably impossible to know [...] what food is healthy for you," and explained,

You can only use observational studies, you can't show cause and effect, and it's incredibly complicated. And major epidemiologists talking about lots of areas think that it's probably impossible to tell what's healthy and what's not healthy in terms of lifestyle from the studies that we have. It's a fact that's frustrating, one would like to obviously know and the desire to know is so great that people are willing to imagine they know even when they don't know, but it's really hard to make any statement about the healthiness of a type of food [...]

Observational studies (as opposed to controlled experiments in which different groups of people are assigned to different behaviors, which are very difficult to conduct in the case of diet), he said, can reveal large effects like the effect of smoking on health. But the effects of different foods are likely so small by comparison that "There's no way that you can separate that out from the other factors and so it's quite likely that we don't know and we'll never know what are good foods to eat." For those who consider themselves healthy eaters, this sounds disheartening — and certainly many people, both in medicine and in the food industry, would likely disagree. But Bratman also pointed me to an essay he originally published in 1997, in which he chronicled his own struggle with orthorexia and critiqued alternative medicine's excessive reliance on dietary restriction. He wrote,

Dietary methods of healing are often offered in the name of holism, one of the strongest ideals of alternative medicine. No doubt alternative health practitioners are compensating for the historical failure of modern medicine to take dietary treatment seriously enough. But by focusing single-mindedly on diet, such practitioners end up advocating a form of medicine as lacking in holistic perspective as the more traditional approaches they attempt to correct. It would be far more holistic to try to understand other elements in the patient's life before making dietary recommendations, and occasionally to temper those recommendations with that understanding.

This last seems like good advice for traditional doctors as well, and indeed, for anyone: diet can be an aspect of health, but it isn't everything, and when "healthy" eating gets in the way of living, it can be more a disease than a cure.